I would try a radical approach. Chevy, covering cars and truck/suv's from 12000 to about 30000 max. Practicle familly oriented cars/trucks (Like Toyota) and affordable performence. Caddy covering cars and truck/suv's from 30000 up to whatever. Luxury to hyper performence. Opel - Euopean style cars. Subaru - Asian style cars. Get rid of everything else. Later on infuse Chevy and Caddy into Europe/Asia and then eventually dump Opel/Subaru. You will end up like Toyota/Honda Chevy is your world wide everyman vehicles and Caddy your worldwide Luxury vehicles. All engineering design focused on two lines. A leaner more efficient management. Of course it's not going to happen and Toyota will eventually take over the world.